The air bleed screw should be around two turns, make sure hole is clear. Take a fuel bulb and back flush from Carb to inlet side of needle valve, make sure to catch fuel in small bottle. If that doesn't do it check the plactic piece where it goes into carb. Checl bottle for forign objects then you can blow through carb with crank in closed position. I had a same problem with 46LA and one of thosed fixed it. Jim
PS make sure needle valve is four or more turns open before back flushing.